The present invention relates to a snap switch, or so-called "positive safety" switch, wherein a greater pressure on the control button of the switch necessarily switches off the electric circuit.
The invention relates more particularly to a snap switch, comprising a control button, a control rod slidable with the control button via a spring, two pairs of contacts associated, respectively, with two pairs of terminals, the two contacts of each pair of contacts being connectable by resilient conducting means under the action of a setting spring fixed to the control rod and to these means, the two contacts of one pair of contacts being able to be electrically disconnected from their respective terminals by the control button when it is pushed in completely against the action of the spring of the control rod.
Such a switch is described, as a whole, in German Pat. No. 2 551 873 (FIG. 1), German Pat. No. 2 551 858 (FIG. 1 ) and in British Pat. No. 1 114 630 (FIGS. 1 and 2).
However, although these latter switches enable the electric circuit to be switched off when the main contacts are welded, they present the drawback of not necessarily being able to return these main contacts into working order, in the case of these latter adhering only by microwelds further to an electric arc.